Asthma Flashcards

1
Q

what is a drug history used as part of?

A

Used as part of medicines reconciliation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the 3 types of inhalers?

A

pMDI, dry powder and breath actuated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what group of patients is a pMDI useful for?

A

Good for majority of patients, but tricky for elderly and children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what group of patients is a dry powder inhaler useful for?

A

useful for patients over 5 years

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What group of patients is a breath actuated inhaler useful for?

A

Better for older children and adults

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

describe the inhaler technique

A

First test inhaler by: removing cap; check dose counter, and point inhaler away from you and press canister once. To use:shake inhaler, make sure you are sat/standing upright with chin slightly tilted upwards, breath out gently away from the inhaler until lungs feel empty, then place mouthpiece between lips to form tight seal and start to breath in slowly and steadily. At the same time, press the canister once and continue to breath in until lungs feel full. Remove inhaler, and with lips closed, hold breath for up to 10 seconds then breath out. when finished, replace the cap.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

why should you slightly tilt chin up when using an inhaler?

A

This helps the medicine reach the lungs better

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

explain the neural control of ventilation

A

Peripheral chemoreceptors detect changes in pH, pCO2 and pO2. Impulses are sent to respiratory centre via sensory nerves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the normal heart rate range?

A

Between 60-100bpm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

describe the regulation of ventilation

A

Respiratory centre consists of inspiratory and expiratory groups of neurons. These are regulated by the pneumotaxic centre.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

describe what occurs during inhalation

A

The diaphragm contracts (moves down)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

describe what occurs during exhalation

A

the diaphragm relaxes (moves up)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the importance of immunology?

A

many drugs use the immune system to treat diseases (autoimmune, cancer, allergic contact dermatitis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Give examples of drugs used in immunology

A

monoclonal antibodies, anticytokine therapies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

define immunology

A

the discipline of medicine concerned with: structure and function of immune system, innate and acquired immunity, and bodily distinction of self

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is key in immunology?

A

Communication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Give examples of physical and chemical barriers in immunology

A

skin, sebum, tears and sweat (lysozyme in tears), GI, respiratory and genito-urinary tracts are lined with mucous membranes which secrete mucous to trap microbes, ciliated epithelia in GIT to trap microbes, saliva and urine wash away microbes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the primary lymphoid tissues?

A

Bone marrow (B cells), thymus (t cells), lymphocyte development and haematopoiesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does the lymphatic system consist of?

A

primary lymphoid tissues, secondary lymphoid tissues, tertiary lymphoid tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are secondary lymphoid tissues?

A

spleen, lymph nodes, gut associated lymphoid tissue and peyers patches, tonsils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What occurs in secondary lymphoid tissues?

A

Site where lymphocytes congregate and adaptive immune responses are initaited

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what does the thymus consist of?

A

Cortex and medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Describe the structure of the cortex

A

packed with immature thymocytes from bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

describe the structure of the medulla

A

cellular ‘mesh’ which makes up the thymus called stroma and comprises t-lymphocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are the 2 major roles of the thymus?

A
  1. secretion of growth factors to mature thymocytes- maturation to t helper and t cytotoxic cells
  2. exposure of thymocytes to self epitopes on stroma- t cells recognising self die via apoptosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Describe the structure of the spleen

A

Highly vascular and composed of red and white pulp (lymphoid tissue) and periarterial sheath (mostly t cells), has a marginal zone (many b cell follicles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are lymph nodes?

A

Immunological filter allowing contact between antigen and immune cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what are lymph nodes composed of?

A

cortex, paracortex and medulla

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

what does the cortex consist of in lymph nodes?

A

dendritic cells presenting antigen and B cell follicles, where B cells proliferate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

what does the paracortex in lymph nodes consist of?

A

many t cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

what occurs in the medulla of lymph nodes?

A

area of B cell antibody secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

where are lymph nodes located?

A

adjacent to GI and respiratory tracts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what does malt stand for?

A

Mucosa associated lymphoid tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what are mucosa associated lymphoid tissue?

A

diffuse system of small concentrations of lymphoid tissue found in submucosal membrane sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What do MALT consist largely of?

A

consists largely of groupings of lymphoid follicles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Give examples of MALT

A

Tonsils, appendix, peyers patches

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

what is essential for an effective immune system?

A

Communication between cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

what are the types of cells present in the immune system?

A

granulocytes, mononuclear cells, macrophages, dendritic cells, natural killer cells and NKT cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Give examples of granulocytes

A

neutrophils, eosinophils, basophils and mast cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

give examples of mononuclear cells

A

lymphocytes, monocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

what are the 2 types of immune response?

A

innate and adaptive immunity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

what are the characteristics of innate immunity?

A

inborn and non specific

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

what does adaptive immunity consist of?

A

memory, specificity, and includes cell mediated and antibody mediated responses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Give examples of cells involved in innate immunity

A

dendritic cells, mast cells, macrophages, basophils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Give examples of cells involved in adaptive immunity

A

B cells, t cells, antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Give examples of cells involved in both innate and adaptive immunity

A

T cells, Natural killer T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What are neutrophils and what is their role?

A

predominant granulocyte cell (consists of 60% circulating cells)
first cells to arrive at site of infection and engulf and destroy infectious agents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

what are eosinophils and what is their role?

A

Contain cytoplasmic granules (eg. major basic protein) and eosinophil perioxidase
important for parasitic infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What are basophils and what is their role?

A

minor cell population, role largely unknown but thought to play role in allergy through histamine release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

what are mast cells and what is their role?

A

contain histamine and cytokines, and generate eicosanoids which are key to allergic reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What are B lymphocytes and what is their role?

A

Develop in bone marrow and mature in spleen
prior to antigen exposure, they are not yet producing antibody (naive)
after exposure, they proliferate and develop into plasma cells, producing increased levels of antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

where are T lymphocytes developed?

A

In the thymus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What are monocytes and what is their role?

A

precursors of tissue macrophages and dendritic cells

infiltrate tissue at site of infection and eliminate debris

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is the role of macrophages?

A

phagocytose unwanted material and then present the antigen to T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What are dendritic cells and what is their role?

A

have long dendrites that can interact with many cells

highly efficient antigen presenting cells, derived from myeloid or lymphoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

what are natural killer cells and what is their role?

A

large lymphocyte lineage cells which kill other cells on contact.
kills tumour cells and some virus infected cells and recognise targets by low/no MHC I expression.
react against microbial antigens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

what is involved in immune cell signalling?

A

lipid mediators, polypeptide factors and cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

Give examples of lipid mediators?

A

eicosanoids, prostaglandins and thromboxanes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

what side effects do platelet activating factors have?

A

muscle contraction, sleep disturbances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

give examples of polypeptide factors

A

cytokines, complement and acute phase proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

how do cytokines act?

A

act via autocrine, paracrine or signalling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

define antigen

A

immunogen or a hapten foreign to body that evokes an immune response, either alone or after forming complex with larger molecule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

what are antigens capable of?

A

capable of binding with product (as an antibody or t cell) of the immune response
‘the on/off switch of the immune system’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

define epitopes

A

parts of the antigen recognised by the immune response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

what is the goodness of fit of an antigen to antibody important for?

A

important in determining strength of binding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

What could occur if an epitope is a low affinity binder to an antibody?

A

its possible that the antibody could bind to another similar epitope- cross reactivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

describe the factors contributing to immunogenicity of antigens

A

size (higher than 1kDA otherwise haptens), difference from self, dose and class (carbohydrate, lipid, nucleic acid and proteins)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

what are antibodies?

A

soluble proteins that bind to antigens, can exist as membrane form and function as a B cell receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

what are idiotypes?

A

antibodies which vary in the variable region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

what does the variable region occupy?

A

occupies about 110 amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

what are the classes of antibody in humans?

A

IgM, IgD, IgG, IgE, IgA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What can produce the 5 classes of antibody?

A

B lymphocytes can produce all 5, but 1 at a time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

what is IgG?

A

most abundant immunoglobulin in serum and consists of 4 subtypes (isotypes)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

what are isotypes?

A

antibodies which vary in the constant region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What are the functions of IgG?

A

Transplacental transfer, agglutination, activation of complement, antibody dependant cytotoxicity, neutralisation and opsonisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

what is IgM and where does it exist?

A

Exists in 2 forms

  1. on surface of B lymphocytes as a single IgG like molecule
  2. in the circulating plasma as a pentameric (5 IgG like molecules) form
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What are the functions of IgM?

A

very good agglutinator of antigens, foetal protection and activation of complement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

What is IgA and how does it exist?

A

exists as a monomer or dimer with a J chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What are the functions of IgA?

A

Protects mucosa- only antibody that can be secreted in any quantity across mucosa. to do so, it requires ‘secretory piece’ which acts as a suicidal transporter
neonatal protection from enteric pathogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

what is IgE and what are the functions?

A

similar to IgG but longer

Major role in asthma and allergy, and protection against parasitic infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What is IgD and what are the functions?

A

produced along with IgG and serves as a B cell receptor and marker
Activates basophils to release antimicrobial factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

Describe the recognition of antigen by lymphocytes

A

Antigen binds to BCR or TCR to allow lymphocytes to proliferate and recognise the same antigen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

what receptors regulate mucus secretion?

A

Muscarinic receptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What are muscarinic receptors involved in?

A

muscarinic receptors are G protein coupled and are involved in: bronchoconstriction and increase mucus secretion at the neuroeffector junction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What are the main type of muscarinic receptors in the airways?

A

M3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

does sympathetic innervation occur in the airways?

A

No sympathetic innervation although there are B2 adrenergic receptors that respond to adrenaline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

what does the autonomic nervous system consist of?

A

Parasympathetic and Sympathetic nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

what are the functions of the lower respiratory tract?

A

distribution of air to alveoli, cleanse, warm and moisten air, and in mucus production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What surrounds bronchioles?

A

bronchioles have bands of smooth muscle surrounding airways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

what does transmission at neuromuscular junction occur between?

A

occurs between a motor neuron and voluntary muscle

Forms part of the somatic nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

how does transmission at neuromuscular junction occur?

A

somatic motor neuron releases Ach at neuromuscular junction. Net entry of Na+ through Ach receptor channel initiates a muscle action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

How does the regulation of intracellular Ca- occur?

A

Through negative feedback

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

what does curare cause?

A

causes muscle paralysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

what is tubocurarine used for?

A

a skeletal muscle relaxant to secure muscle relaxation in surgical procedures without deep anesthesia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

give an example of a long acting non depolarizing muscle relaxant

A

Pancuronium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

Give an example of an intermediate acting non depolarizing muscle relaxant

A

Atracurium, vecuronium, rocuronium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

Give an example of a short acting non depolarising muscle relaxants

A

Mivacuronium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

What is the mechanism of action of non depolarising muscle relaxants

A

bind nicotinic Ach receptors and competitively block acetylcholine, preventing muscle contraction
they are competitive antagonists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

How can the block of acetylcholine be overridden in non depolarising muscle relaxants?

A

By the addition of cholinesterase inhibitors, which increases the concentration of Ach in synapse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

What is the main use of non depolarising muscle relaxants?

A

Mainly used as an adjunct in anaesthesia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

What are depolarising neuromuscular blockers?

A

Eg. Suxemethonium- not overcome by anti-cholinesterases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

What are the 2 types of therapy used as a treatment for asthma?

A

controllers/preventers taken daily on long term basis to keep asthma under control, and relievers (rescue medication) used as needed to reverse bronchoconstriction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

What are short acting beta 2 antagonists?

A

SABA, reliever- step 1

e.g salbutamol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

What are long acting beta 2 antagonists?

A

LABA, preventers- step 3

e.g salmeterol and formoterol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

define bronchodilate

A

relax airway smooth muscle and increase airflow to the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

What is the mechanism of action of beta 2 antagonists?

A

stimulate B2 adrenoreceptors and relax smooth muscle by raising cyclic AMP levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

What are the functions of beta 2 antagonists?

A

decrease production of inflammatory mediators from immune cells and increase mucocilliary clearance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

What are inhaled corticosteroids classed as?

A

Preventers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

When are inhaled corticosteroids used?

A

if a patient has experienced an exacerbation in the past 2 years; uses short acting beta 2 agonist 3< times per week; experiences asthma symptoms 3< times per week; wake up at least 1 night per week with symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

Give an example of an inhaled corticosteroid

A

Beclomethasone, fluticasone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

What are oral corticosteroids classed as?

A

preventers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

When would an oral corticosteroid be used?

A

High dose used in an acute attack, and lowest dose for adequate control of patients who suffer severe persistant/continuous symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

Give an example of an oral corticosteroid

A

prednisolone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

What are the 2 actions of corticosteroids?

A

Anti inflammatory- stop release and formation of inflammatory substances (leukotrienes, prostaglandins)
immunosuppressive- stops proliferation and infiltration of white blood cells into inflamed areas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

Name some side effects of oral corticosteroids?

A

hyperglycaemia, gastric ulcers, osteoporosis, cataracts, glaucoma, and brusing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
116
Q

Name some side effects of inhaled corticosteroids

A

Oral candidiasis, dysphonia and reflex cough

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
117
Q

What are the main side effects of corticosteroids?

A
CORTICOSTEROIDS:
Cushings syndrome
osteoporosis
retardation of growth
thin skin and easily bruising
infections and immunosuppression
cataracts and glaucoma
odema
suppression of hypothalamic pituitary adrenal axis
thinning and ulceration of gastric mucosa
emotional disturbance 
rise in bp
increase in hair growth
others like fetal abnormalities and hypokalaemia
diabetes mellitus precipitation
stria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
118
Q

Describe step 3 of treatment of asthma

A

LABA used in combination with inhaled corticosteroid (never alone)
eg. Seretide: salmeterol and fluticasone; Symbicort SMART: budesonide and formoterol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
119
Q

what is step 4 of treatment of asthma?

A

Add on therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
120
Q

Give examples of add on therapy used in step 4

A

Methylxanthines, leukotriene antagonists, cromoglycates

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
121
Q

What are oral/IV methylxanthines classed as?

A

Reliever and preventer, depending on formulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
122
Q

Give an example of an oral/IV methylxanthine and when it would be used?

A

Theophylline (oral) used in step 5 and aminophylline (IV) used for acute exacerbations of asthma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
123
Q

Why is it important to use the same brand of theophylline in asthma treatment?

A

due to differences in bioavailability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
124
Q

What are the clinical effects of oral/IV methylxanthines?

A
  1. bronchodilation by: inhibiting breakdown of cAMP, and acting as an antagonist at adenosine receptors
  2. increased muco-ciliary clearance
  3. antiinflammatory effects- inhibits eosinophils
  4. reduces histamine and IL release from mast cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
125
Q

Describe the theapeutic range of methylxanthines and what this may cause?

A

narrow therapeutic range- can cause seizures and arrhythmias

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
126
Q

What are leukotriene receptor antagonists classed as?

A

preventer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
127
Q

Give examples of leukotriene receptor antagonists

A

Zafirlukast and montelukast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
128
Q

What are the functions of leukotriene receptor antagonists?

A

oral therapy taken at night. Relax airways and reduce mucus secretion, and inhibit exercise/aspirin induced asthma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
129
Q

What are lipoxygenase 5 antagonists used for?

A

prevent production of leukotrienes (eg zilutin)

little used due to liver side effects

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
130
Q

What are cromoglycate and Nedocromil classed as?

A

preventers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
131
Q

How is cromoglycate administered?

A

given by aerosol inhalation, nebules and powder

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
132
Q

how is nedocromil administered?

A

by aerosol inhalation, as it has no direct effect on smooth muscle given prophylactically

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
133
Q

What are the roles of cromoglycate and nedocromil?

A

reduce bronchila hyper reactivity, and effective in antigen induced, exercise induced and irritant induced asthma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
134
Q

What must be noted before giving cromoglycate and nedocromil?

A

children more likely to respond than adults, and must be given before exposure to allergen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
135
Q

what is step 5 of asthma treatment?

A

daily oral corticosteroids at lowest dose possible for shortest amount of time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
136
Q

what is omalizumab classed as?

A

preventer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
137
Q

what is omalizumab and how is it administered?

A

monoclonal antibodies, brand name= xolair, given as injection every 4 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
138
Q

what is omalizumab used for?

A

used to treat moderate/severe persistant asthma in those whose symptoms are not well controlled with inhaled corticosteroids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
139
Q

what is the mechanism of action of omalizumab?

A

binds free IgE in the serum, forming trimers and hexamers
drug binds to IgE at the same site that high affinity IgE receptor binds, so, IgE bound to drug cant bind its receptor on mast cells and basophils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
140
Q

what is the elimination half life of omalizumab?

A

7 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
141
Q

where is omalizumab metabolised/eliminated?

A

by liver

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
142
Q

describe the acquisition of antigen

A

foreign antigen enters body through skin, respiratory and GIT. Cells will pick up antigen and transport it to peripheral lymphoid tissues where adaptive immune responses are initiated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
143
Q

describe how adaptive repsonses occur?

A

antigen has to be presented to lymphocytes in organised lymphoid tissue by antigen presenting cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
144
Q

what must immature dendritic cells do in adaptive responses?

A

immature Dendritic cells cant activate t cells, so must encounter antigen first, digest antigen into small peptide fragments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
145
Q

give examples of antigen presenting cells

A

macrophage, dendritic cells, langerhans cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
146
Q

describe the process of dendritic cell maturation

A

immature dendritic cells become mature dendritic cells with increased MHC II and other receptors on its surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
147
Q

what are dendritic cells responsive to?

A

cytokines and chemokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
148
Q

what are the 4 main subfamilies that chemokines are grouped into?

A

CXC, CC, CX3C and XC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
149
Q

What is the role of chemokines?

A

these proteins exert biological effects by interacting with G protein coupled receptors, that are selectively found on the surface of target cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
150
Q

what is the major histocompatibility complex MHC?

A

set of cell surface proteins essential for acquired immune system to recognise foreign molecules in vertebrates, which determines histocompatibility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
151
Q

what is the main role of MHC?

A

to bind to antigens derived from pathogens and display them on cell surface for recognition by appropriate t cells
also deterimines compatibility of donors for organ transplants and susceptibility ro an autoimmune disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
152
Q

What are the 3 types of MHC?

A

MHCI, MHCII, MHCIII

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
153
Q

What are the MHC class I genes?

A

HLA-A, HLA-B, HLA-C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
154
Q

what are the MHC class II genes in humans?

A

HLA-DP, HLA-DQ, HLA-DR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
155
Q

What are the MHC class III genes?

A

C2, C4 and factor b

encodes TNF and complement factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
156
Q

how does the cleft size differ in MHC I and II?

A

type I= 8-10 amino acids long

type II= 12-18 amino acids long

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
157
Q

Where is class I MHC found and what is its role?

A

found on all cells (except RBCs and neurons), known as transplantation Ag
presents endogenous Ag and interacts with CD8 on t cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
158
Q

where is class II MHC found and what does it present?

A

found only on antigen presenting cells, presents exogenous Ag
interacts with CD4 on t cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
159
Q

describe how MHC is involved in organ transplant process

A

determines whether an organ transplant is rejected or accepted
organ rejection is normal, as the immune response is directed towards non self MHC molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
160
Q

describe the role of MHC

A

t cell only recognises antigen when its presented by an antigen presenting cell that has a particular MHC molecule- MHC restriction
applies to CD8 t cells recognising MHCI and CD4 recognising MHCII

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
161
Q

Where is CD4 found?

A

found on t helper cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
162
Q

where is CD8 found?

A

found on t-cytotoxic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
163
Q

what does the relationship between MHC and CD4/8 define?

A

the type of immunological reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
164
Q

describe an endogenous antigen immune response

A

(intracellular-virus, parasite, cancer marker)- MHC class I presentation, CD8 and TCR recognition, activation T cytotoxic cells, killing of infected cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
165
Q

describe what occurs in an exogenous antigen immune response?

A

(extracellular- bacterium, parasite, extracellular virus phase)- MHC class II presentation, CD4 and TCR recognition, activation of T helper cells, cytokines released to help B cells produce antibody

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
166
Q

what are the 2 major pathways where antigens are processed and presented to t cells?

A

exogenous- taken up from outside the cell and presented to MHC II
endogenous- made up inside the cell and presented to MHC I

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
167
Q

what are naive cells?

A

those which are meeting antigen for the 1st time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
168
Q

what are effector cells?

A

those which have gone through Ag stimulation and become activated, proliferate and ready to kill target cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
169
Q

what other accessory molecules are involved in t cell activation?

A

LFA1-ICAM1 are adhesion molecules, CD28 is a critical receptor for B7-1 and B7-2 before stimulation
after stimulation, CD28 becomes CTLA-4 which inhibits further reactivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
170
Q

What cells are involved in innate immunity?

A

polymorphonuclear leukocytes (PMNs, polymorphs, neutrophils), effector cells with cytotoxic granules (perforin/granzymes), M1 (pro inflammatory) and M2 (anti inflammatory), capture debris (APC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
171
Q

describe the characteristics of polymorphonuclear leukocytes

A

very aggressive, short lived cells with characteristic multilobed nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
172
Q

describe the characteristics of effector cells

A

rapid innate immunity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
173
Q

describe the role of M1 and M2 cells

A

promote angiogenesis and favour tumour progression

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
174
Q

describe the role of capture debris

A

activates naive t cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
175
Q

what is the role of epithelia?

A

impose physical barrier between body and external milieu

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
176
Q

what do epithelial surfaces comprise of?

A

comprise of skin and linings of bodys tubular structures, GI, respiratory and urogenital Tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
177
Q

describe the structure of the skin

A

outer layers of epidermis consists of the stratum corneum, which consists of dead corneocytes, full of keratin, seperated by lipid layers (landmann units).
this creates waterproof and impermeable layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
178
Q

what occurs if keratinocytes are damaged?

A

produce TNF and IL-8 which leads to inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
179
Q

what occurs on mucosal surfaces?

A

mechanical protection via a layer of mucus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
180
Q

what are mucosal surfaces used for in the airway?

A

the mucociliary escalator moves mucus and trapped particles to the throat to swallow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
181
Q

what is the role of the mucosal surfaces in the stomach?

A

the mucus protects gastric mucosa from stomach acid and enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
182
Q

what is the role of the mucosal surfaces in the uterine cervix

A

protects uterus from bacterial invasion

breach by old style IUD threads could lead to pelvic inflammatory disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
183
Q

what is the role of mucosal surfaces on the eyes?

A

on the eyes corneal surface, it protects the corneal epithelium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
184
Q

what occurs when a virus makes it into a cell?

A

antibodies cant bind to them anymore to prevent its entry, so something must be able to recognise virally infected cells and eliminate it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
185
Q

give examples of the types of T cells

A

T helper cells, cytotoxic lymphocytes and t regulatory cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
186
Q

what is the difference between t cells and b cells?

A

t cells can also recognise antigens, but unlike b cells, these antigens can only be protein fragments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
187
Q

describe how t cells work

A

t cell receptor recognises and binds simultaneously to the foreign protein fragment and to the self protein (MHC) on the surface of affector protein cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
188
Q

what are pattern recognition molecules and what are they used for?

A

IMS is armed with pattern recognition receptors that recognise pathogen associated molecular patterns (PAMPs) not found in host, then activates immune response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
189
Q

what are the 5 families that PRRs are classified into?

A
  1. toll like receptors (tLRs)
  2. nucleotide binding and oligomerisation domain (NOD) like receptors (NLRs)
  3. retinoic acid inducible gene 1 (RIG 1) like receptors (RLRs)
  4. C type lectins (CTLs)
  5. absent in melanoma (AIM) like receptors (ALRs)
190
Q

where are TLRs and CTLs located?

A

in the plasma membrane

191
Q

what are NLRs, RLRs and ALRs

A

intracellular PRRS

192
Q

What are NLRs?

A

cytoplasmic receptors that play critical role in IMR by recognising PAMPs and damage associated molecular patterns (damps)

193
Q

what 4 families does NLRs exist as?

A

NLRA, NLRB, NLRC, NLRP

194
Q

what are the 4 functional categories that NOD-like molecules are divided as?

A
  1. inflammasome assembly
  2. signal transduction
  3. transcription activation
  4. autophagy
195
Q

what are natural killer cells used for?

A

kill virally infected cells or tumours that have reduced MHC class I expression

196
Q

what are the chemokines responsible for as inflammatory mediators?

A

group of peptides responsible for control of migration of leukocytes (noming) in the respective anatomical locations in inflammatory and homeostatic processes

197
Q

how are chemokines up regulated?

A

by number of cytokines involved in infection and inflammation
- y interferon and TNF-a

198
Q

what are the 4 types of chemokines?

A

CC type, CXC type, CX3C type and C type

199
Q

what are the 4 types of chemokines produced by and what do they affect?

A

produced by number of cell types and affect mostly leukocytes (especially lymphocytes) via chemokine receptors

200
Q

what are the 5 chemokine functions?

A
  1. monocytes/macrophages (eg CCL chemokines CCL2)
  2. t cells (CCL2, CCL1, CCL22, CCL17)
  3. mast cells- express several receptors for chemokines (CCR1, CCR2, CCR3, CCR4, CCR5, CXCR2, CXCR4)
  4. eosinophils- migration of eosinophils into tissues involves CCL11, CCL24, CCL26, CCL5, CCL7, CCL13 and CCL3)
  5. neutrophils- regulated mostly by CXC chemokines
201
Q

what occurs following t cell activation in regards to chemokines?

A

CXCR3 expression is induced
activated t cells are attracted to sites of inflammation, where the inducible chemokines CXCL9, CXCL10 and CXCL11 are secreted

202
Q

why are ligands of receptors CCL2 and CCL5 important?

A

play important role in mast cell recruitment and activation in lung

203
Q

how do CCL11 and CCL5 act?

A

through CCR3 on surface of eosinophils

204
Q

why is eotaxin (CCL11) important?

A

plays role in initial recruitment of eosinophils into the lesion

205
Q

what is the role of CXCL8?

A

a chemoattractant for neutrophils and also activating their degranulation

206
Q

what is the complement system?

A

part of immune system that enhances ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promoting inflammation and attacks membrane

207
Q

what is the complement system a part of and what is it made up of?

A

part of IMS
made up of number of small proteins (consists of 30 soluble proteins) found in blood, synthesised by liver and normally circulating as inactive precursors (pro-proteins)

208
Q

what happens when complement system is stimulated?

A

proteases in system cleave specific proteins to release cytokines and initiate an amplifying cascade of further cleavages

209
Q

what is the complement system designed to do?

A

an effector mechanism designed to kill target cells and regulates inflammatory responses by enhancing phagocytosis and WBC recruitment

210
Q

what are many components of the complement system secreted as?

A

many components secreted as zymogens and are activated by proteolysis

211
Q

what are the 3 pathways complement activation occurs?

A
  1. classical pathway- activated by antibody attached to antigen
  2. alternative- activated by cell surfaces unable to inhibit complement
  3. lectin- activated by mannose binding lectin
212
Q

what was complement discovered as?

A

discovered as a heat labile component of plasma which augment the opsonisation and killing of bacteria by antibodies

213
Q

define opsonisation

A

coating of pathogen by antibodies or complement proteins, so its readily destroyed by phagocytic cells

214
Q

What does complement also influence?

A

influences AIS (t and B cells)

215
Q

what does complement system recognise?

A

recognises features of microbes and marks them for destruction by phagocytes by C3b

216
Q

What does the classical pathway of complement activation require?

A

requires presence of antibodies (IgM or IgG)

217
Q

when is the lectin pathway initiated in complement activation?

A

initiated during inflammatory responses upon contact with bacterial surfaces

218
Q

what are the 2 types of pulmonary drug delivery?

A

local and systemic

219
Q

what are the characteristics of local delivery

A

rapid onset of action, small doses

220
Q

give examples of systemic delivery

A

inhaled anaesthetics, insulin

221
Q

give examples of local delivery

A

B2 agonists, corticosteroids, anticholinergics

222
Q

what can be used to help drugs get into the lungs?

A

inhalers, nebulisers

223
Q

name the different types of inhalers

A

pMDI, DPI, and soft mist inhalers (respimat)

224
Q

define aerosol

A

a 2 phase system of solid particles or liquid droplets dispersed in air or other gaseous phases

225
Q

what does airway deposition depend on?

A
  1. physicochemical properties of drug- particle size, shape and density
  2. formulation- pMDI, dry powder
  3. delivery/liberating device- aerosol velocity
  4. patient- breathing patterns, clinical status
226
Q

define aerodynamic

A

the dynamics of bodies moving relative to gases, especially the interaction of moving objects with the atmosphere

227
Q

define aerodynamic diameter

A

the physical diameter of a spherical particle with unit density (1g cm-3) that has the same inertial properties (terminal settling velocity) in the gas as the particle of interest

228
Q

equation to calculate aerodynamic diameter

A
Da= dp(P/Po)^1/2
dp= physical diameter
Po= unit density
p= particle density
229
Q

what are therapuetic aerosols classed as

A

heterodisperse

230
Q

what is the distribution of sizes represented by in mass median aerodynamic diameter?

A

represented by geometric standard deviation, when size is log-normally distributed

231
Q

when dp is mass median diameter, what is Da?

A

da= Mass median aerodynamic diameter

232
Q

what does particle deposition depend on?

A

aerodynamic diameter

233
Q

what are the mechanisms of particle deposition?

A

inertial impaction, sedimentation, brownian diffusion, interception

234
Q

what is the probability of deposition via impaction dependent on?

A
dependent on momentum of particle and also proportionate to angle: VtVsino/Gr
Vt= terminal settling velocity
o= change in airway direction
V= air stream velocity
r= airway radius
235
Q

equation for momentum of particle

A

momentum= mass x velocity

236
Q

what is sedimentation

A

setlling under gravity, airflow is low

237
Q

where does impaction take place?

A

upper tracheobronchial region

238
Q

what is stokes law

A
Vt= pgd^2/18n
Vt= terminal settling velocity
p= particle density
g= gravitational constant
d= particle diameter
n= air viscosity
239
Q

where does sedimentation occur in the lungs?

A

small airways and alveoli

240
Q

what is sedimentation dependant on?

A

dependent on particle size and density and residency time in the lung

241
Q

where does diffusion take place in the lung?

A

in the alveoli

242
Q

describe the particle density of large porous particles

A

physical diameter-20um and density- 0.4gcm-3

efficient deposition in the lungs

243
Q

what do breathing patterns depend on?

A

inhaled volume, flow rate of inhalation, breath holding and airway disease

244
Q

Describe what was found in lung deposition studies

A

assesed regional distribution of inhaled compound
quantify patients influence on deposition
use technetium labelled drug and use gamma scintigraphy
provide a picture of deposition

245
Q

what are the different methods of aerosol size analysis?

A
  1. gamma scintigraphy- in vivo direct measurement
  2. microscopy- in vitro, labour intensive, not moving air stream
  3. laser diffraction- in vitro, volume median diameter
  4. cascade impaction- in vitro, aerodynamic particle diameter
246
Q

describe what an anderson cascade impactor involves

A

known flow rate, 90 degree bend and generally has 8 stages. involves metal collection plates and terminal filter

247
Q

what are the disadvantages of anderson cascade impactors

A
  1. high flow rates- rapid solvent evaporation, particles bounce off collection surfaces
  2. constant air flow rate- not representative of in vivo
  3. time consuming
248
Q

what are the 3 main types of aerosol generating devices?

A
  1. pressurised metered dose inhalers
  2. dry powder inhalers
  3. nebulisers
    - technique depends on the device being used
249
Q

describe the material containers of pMDIs

A

must be chemically inert
tin plated steel, plastic coated glass, uncoated AL, Al with internal coating of epoxy resin or PTFE
extruded al to avoid seams
can withstand internal pressure of >400kPa
capacity= 10-30ml

250
Q

describe what a pMDI propellant is and how they work

A

Liquified gases (CFCs replaced by HFAs), work though a constant pressure system and producing a consistant spray

251
Q

what is the evaporation of a liquid?

A

saturated vapour pressure

252
Q

how are formulations generally made up?

A

generally made up of blends of the propellants together to give an intermediate vapour pressure of 450kPa

253
Q

what does the blending of propellants include?

A

include a surfactant (eg sorbitan trioleate, oleic acid) which acts as a suspending agent for the drug and lubricates the valve

254
Q

describe the solubility of surfactants in the blending of propellants

A

poorly soluble in HFAs

255
Q

give examples of hydroflourocarbons

A

HFA134a (triflouromonoflouroethane), HFA227 (heptaflouropropane)

256
Q

describe the characteristics of hydroflourocarbons

A

non ozone depleting, non flammable, density similar to CFC12 and CFC114, but poor solvents for surfactants commonly used in MDI formulations

257
Q

describe how ethanol may be used with HFAs

A

ethanol is approved for use in formulations containing HFAa tp allow dissolution of surfactants, but has low volatility and may increase droplet size of emitted aerosol

258
Q

what effect does a smaller particle size have?

A

smaller particle size can change pulmonary distribution and bioavailability

259
Q

what is Rauoults law and ideal mix of liquids?

A

the partial vapour pressure of a component in a mixture is equal to the vapour pressure of the pure component at that temperature multiplied by its mole fraction in the mixture

260
Q

equation for Raoults law

A

p= pA + pB
p= total vapour pressure of system
pA and pB= partial vapour pressure of components A and B in the mixture

261
Q

equation for partial vapour pressure

A
PA= XA x P^oA
Xa= mole fraction
P^oA= partial vapour pressures of A and B as if they were on their own
262
Q

what is the vapour pressure of a mixed system equal to?

A

equal to the sum of mole fraction of each component multiplied by its vapour pressure

263
Q

describe what a pMDI metering valve is and how it is used

A

reproducible delivery of small volumes (25-100ul)
used inverted and needs to be primed
affects shape and speed of aerosol plume

264
Q

what are the formulations of pMDIs?

A

solutions or suspensions of drug in liquefied propellant

265
Q

describe the properties of pMDIs formulated as solutions

A

2 phase systems- propellants are poor solvents, cosolvent (eg ethanol) have low volatility

266
Q

describe the properties of pMDIs formulated as suspensions

A

3 phase systems- caking, agglomeration and particle growth

particle size, valve clogging, moisture content, relative density of drug and propellant

267
Q

what are the 3 ways of filling pMDI canisters?

A

cold filling, pressure filling and leak testing

268
Q

describe the process of cold filling pMDI canisters

A

drug excipients and propellants chilled to -60C, and canister then sealed with valve

269
Q

describe the process of pressure filing pMDI canisters

A

concentrated solution or suspension of drug in propellant, under pressure filled into canisters via the valve

270
Q

describe the process of leak testing to fill pMDI canisters

A

water bath at 50-60C, weighing after storage prior to insertion into actuators and spray testing

271
Q

what are the advantages of pMDIs

A

portable, many doses, reproducible dose delivery, low cost, disposable, inert conditions

272
Q

what are the disadvantages of pMDIs?

A

inefficient drug delivery, incorrectly used, and small doses

273
Q

describe why pMDIs may present inefficient drug delivery

A

upon actuation: high velocity- drug lost due to impaction, mean emitted droplet size >40um, and propellant evaporation slow (5 seconds to achieve desired particle size)

274
Q

describe some areas where patients may incorrectly use a pMDI

A

failure to remove cap, used upside down, failure to shake canister, failure to inhale slowly and deeply, inadequate breath holding, poor inhalation/actuation synchronisation

275
Q

how much of the drug is emitted in pMDI if correct technique used?

A

only 10-20% of emitted dose is delivered to site of action

276
Q

what are spacers useful for?

A

reduce droplet velocity, permit efficient propellant evaporation, and remove the need for actuation/inhalation coordination

277
Q

how are breath actuated pMDIs activated?

A

actuation triggered during inhalation

278
Q

describe the process of adjusting surface roughness of carrier particles

A
  1. microionised drug trapped- low inhaled dose
  2. microionised drug readily released- may release during filling of device
  3. microionised carrier particles to fill rough voids-drug readily released
279
Q

what are the advantages of DPIs

A

propellant free, only 1 excipient (lactose), breath actuated (avoids problems coordinating inhalation with actuation of pMDI), can deliver larger doses than pMDIs, which are limited by size of metering valve

280
Q

what are the disadvantages of DPIs?

A

delivery dependent on patients ability to inhale, turbulence can increase inertial impaction in upper airways, formulation less stable than pMDIs, less efficient than pMDIs

281
Q

name the different DPI devices

A
  1. unit dose devices with drug in hard gelatin capsule- spinhaler, cyclohaler
  2. multidose devices with drug in foil blisters- diskhaler (GSK)
  3. multidose devices with drug preloaded in inhaler- accuhaler, clickhaler
282
Q

when are nebulisers used and how do they work?

A

deliver relatively large volumes and inhaled during normal tidal breathing.
alternative to pMDI and DPI if: drug cant be formulated, or dose is too large

283
Q

what are the 3 main types of nebulisers?

A

jet nebulisers, ultrasonic nebulisers, vibrating mesh nebulisers

284
Q

describe the formulation of nebuliser fluid

A

in water: cosolvents, surfactants (suspensions), stabilizers (antioxidants, preservatives)
iso-osmotic, pH= 3-10
usually sterile isotonic unit doses

285
Q

what are the types of data

A

categorical- (lived/died, underweight/normal/obese)

numerical (age/height/number of medications)

286
Q

why is the use of data important?

A

describes sample and makes an inference about the population

287
Q

what is numerical data?

A
  1. discrete data that can be counted

2. continuous data that can be measured

288
Q

how would you summarise data

A

categorical data= %
numerical data= mean- measure of the average
- also want a measure of variability

289
Q

how could you compare 2 means?

A

null hypothesis- mean 1=mean 2

experimental hypothesis- mean 1< mean 2 and vise versa

290
Q

what are inferential statistics?

A

go beyond describing the sample and is a decision tool for rejecting null hypothesis

291
Q

what are the test hypotheses in inferential statistics?

A

statement about the predicted outcome of study and states the independent and dependant variable

292
Q

what does inferential statistics tell us about probability?

A

will tell you the probability that the effect observed is due to random factor (p value)

293
Q

what does a p value of 1 mean?

A

100% probable that the effect wouldve occured under the null

294
Q

what does a p value of 0.5 mean?

A

50% probable that the effect wouldve occured under the null

295
Q

what does a p value of 0.05 mean?

A

5% probable that the effect wouldve occured under null

296
Q

equation for paired t test

A

t= d/Sd(root of n)

297
Q

what is an independent t test used for?

A

2 seperate groups

298
Q

what types of groups could you use an independent t test for?

A

experimental groups- drugs vs placebo, hot conditions vs cold
naturally occuring groupings (quasi experimental)- young vs old, males vs females

299
Q

when would data violate a parametric assumption?

A

not normally distributed, unequal variance, ordinal data

300
Q

what would be used instead if data violates a parametric assumption?

A

use Mann whitney test instead

301
Q

what are t tests used for

A

to compare the difference between 2 mean scores

302
Q

what is the adaptive immune system and what is it used for?

A

the 2nd level of protection that is activated to enhance the innate system

303
Q

what does the adaptive immune system mainly consist of?

A

mainly consists of lymphocytes

304
Q

what are lymphocytes and what is their role?

A

white blood cells that have the ability to recognise a unique part of a microorganism, memorise it and produce specific pathogen neutralising compounds known as immunoglobulins
so when the body encounters this particular antigen again, it can prodyce more of the immunoglobulins it knows can kill it

305
Q

what is a naive CD4 + t cell called?

A

THO cell

306
Q

what does exposure to antigen cause for a THO cell?

A

exposure to antigen causes differentiation of a THO cell to form t helper subset: Th1, th2, th17, Tregs and Tfh

307
Q

what is the main factor in determining which subset will be produced in the differentiation of THO cells

A

cytokines- these subsets are characterised by cytokines they produce and promote different kinds of immune responses

308
Q

what is the function of TH1?

A

Key for cell mediated immune responses and important against intracellular bacterial infections and viruses

309
Q

what is the function of TH2 cells?

A

key for production of antibodies and control of extracellular bacteria and parasitic worms

310
Q

what is the function of th17?

A

key for cell mediated defense against extracellular bacterial infections via neutrophils

311
Q

what is the function of Treg cells?

A

key for suppressing immune responses and maintenence of tolerance

312
Q

what are the functions of Tfh cells?

A

acquire expression of CXCR5 and important in antibody production

313
Q

what will CD4+ cells differentiate into?

A

will differentiate into short lived effector cells or long lived memory cells

314
Q

what do effector cells provide?

A

provide immediate defense against antigen

315
Q

what do memory cells provide?

A

confer protection after re-exposure to antigen

316
Q

how do effector and memory cells differ?

A

differ by surface marker expression

eg. effector cells express CD69, memory cells express CD45RA

317
Q

how does a t cell receptor recognise antigen?

A

recognises antigen only if it is presented by an MHC molecule on he surface of an antigen presenting cell

318
Q

what group of immune receptors is TCR similar to?

A

immunoglobulin superfamily

319
Q

what are B lymphocytes responsible for?

A

dont kill anything directly, make antibodies

320
Q

what is the role of antibodies secreted by b lymphocytes?

A

antibodies bind to foreign molecules which neutralise their effects. also bind to bacteria which signals other host immune proteins and cells to kill
antibodies secreted by b cells also have a membrane bound form of the antibody on their surface- this antibody acts as a receptor which recognises antigen and through signal transduction process, helps activate B cell

321
Q

what can mature B cells do?

A

can make lots of antibodies quickly, as they have seen antigen before

322
Q

where does B and T cell interaction occur

A

occurs in paracortex of lymph nodes

323
Q

describe the process of B and T cell interaction

A

b cell internalises antigen on b cell receptor and presents fragments of the antigen on MHC II molecules to t cell

324
Q

what does b and t cell interaction require?

A

needs 2 signals binding of TCR to MHC through CD40 and antigen binding to b cell receptor

325
Q

what are the 2 types of b cell response to Ag?

A
  1. thymus dependent response- requires t cell help to deliver antigen to b cell follicles
  2. thymus independent response- doesnt need t cell help
    eg. TLR ligands and microbial polysaccharides that cross link b cell receptors
326
Q

what is class switch recombination?

A

high affinity b cells can interact with antigen specific t cells and under the influence of t cell derived cytokines, undergo isotype switching

327
Q

what is the isotope produced in class switch recombination highly dependent on?

A

highly dependent on cytokine made by t cell

328
Q

describe the generation of CD8+ responses

A

CD8+ cytotoxic t lymphocyte responses (similar to CD4 response)
APCs acquire antigen process and present on MHC class I molecules
antigen MHC I and signal 2 via CD28 which to B7 on APC

329
Q

what is required for CD8+ responses

A

requites 2 signals for activation

330
Q

what is proliferation dependent on in CD8+ responses

A

dependent on IL-2

331
Q

what are effector t cytotoxic cells responsible for?

A

can kill any cell expressing the antigen concerned in association with MHC I

332
Q

what do granules consist of in CD8+ cell killing?

A

perforins and granzymes

333
Q

what is the role of perforins?

A

secreted next to target cell and assemble to form pores in cell membrane, allowing the granzymes to enter target cell

334
Q

what is the role of granzymes?

A

interact with target cells to initiate apoptosis

335
Q

when does primary immune response occur and what happens after elimination of antigen?

A

maximal within 10 days of antigen exposure

after elimination of antigen, 90% of cells die, 10% from memory b and t cells

336
Q

what do memory cells ensure?

A

that the immune response acts more robustly upon re-exposure to antigen

337
Q

when do secondary immune responses occur?

A

maximal within 4 days of re-exposure to antigen hallmark of adaptive immunity

338
Q

describe adherence to inahlers

A

low rates of adherence to controller inhaler associated with hospitalisations and mortality
estimated 50% adherence overall chronic conditions
30-70% adherence to asthma medications
children <50%

339
Q

what are the reasons for non adherence

A

intentional, motivation, non drug reasons, non intentional, ability, drug reasons
difficulty with inhaler devices, side effects

340
Q

describe the needs vs concerns evidence

A

there is evidence that patients make decisions about medicines based on their understanding of their condition and the possible treatments, their view of their own need for the medicine and their concerns about the medicine

341
Q

what strategies can be used for improving adherence?

A

involve patients in decision making (concordance), provide a rationale for regular use, elicit and address concerns, address the practical barriers in a consultation

342
Q

what is the new medicines service and what is it for

A

advanced service that is recently extended. it is a pharmacist led consultation that aims at: providing support for people with long term conditions newly prescribed a medicine to help improve medicines adherence, and to increase patient understanding

343
Q

what does treatment of asthma require?

A

requires combination of pharmacology and psychology

344
Q

why are pharmacist led reviews important

A

offer place for pharmacists to target non adherence

345
Q

define tolerance

A

immunological non reactivity to an antigen, due to lack of response of lymphocytes when exposed to specific antigens

346
Q

what could tolerance result from?

A
  1. deletion- after antigen exposure, lymphocytes may recieve signal to die
  2. antigen exposure may render lymphocytes non responsive
  3. immunological ignorance- antigen may not be immunogenic
347
Q

what is central tolerance

A

process where B and T cells rendered non responsive to self antigens during development in bone marrow and thymus
expression of the Aire gene in thymic medullary epithelial cells is critical for t cell tolerance
major mechanism where autoreactive lymphocytes are removed/silenced so they cant attack self tissues

348
Q

can lymphocytes escape tolerance?

A

some lymphocytes escape tolerance and must be tolerated in the periphery

349
Q

where can b and t cells both be tolerated?

A

both can be tolerated in the periphery

350
Q

what could failure to delete autoreactive CD4 result in

A

may result in cell mediated and antibody mediated autoimmunity

351
Q

how can peripheral tolerance occur

A

may occur as a result of:

  1. deletion- t cells commit suicide (apoptosis), usually as a result of repeated antigen stimulation
  2. anergy (inability to respond)- usually due to lack of co-stimulatory molecules during antigen presentation (stops presentation of antigens by ‘resting’ antigen presenting cells)
  3. suppression- eg Tregs
352
Q

what is the mechanism of deletion?

A

best characterised in the phenomenon of activation induced death by repeated Ag stimulation- occurs when recently activated t cells are repeatedly reactivated
in such situation, t cells express Fas and Fas ligand which binds to each other and induce apoptosis

353
Q

what type of mechanism is deletion?

A

probably a regulation mechanism, but some pathogens shed large amounts of free Ag to stimulate this mechanism

354
Q

describe the mechanism of action of anergy

A

mechanism to prevent response to resting APCs. APCs up regulate co stimulatory molecules when actively phagocytosing pathogens and presenting Ag
- the most important is B7 but rather than expressing CD28, some t cells will express CTLA-4

355
Q

what happens when t cells express CTLA-4 in the mechanism of tolerance of anergy?

A

CTLA-4 when binding to B7 induces anergy. once induced, this type of anergy will persist, even if offered an MHC restricted Ag with B7 co stimulation (normal presentation)

356
Q

describe the mechanism of tolerance of immune ignorance

A

not all self antigens expressed in thymus or bone marrow- some will be in immunologically previledged sites
these will not normally be seen by immune system during life, so no reactivity
eg. lens protein in eye, some heart muscle epitopes

357
Q

what problems can immune ignorance cause?

A

can perhaps cause a problem in trauma to that organ, releasing Ag into circulation

358
Q

when do autoimmune diseases occur?

A

breakdown of tolerance is a pre requisite for development of autoimmune diseases.
autoimmune diseases occur when adaptive immune responses to self antigens contribute to tissue damage

359
Q

what 2 classes are autoimmune diseases divided into?

A
  1. systemic- eg. scleroderma, systemic lupus erythematosus

2. organ specific- eg. graves disease, myasthenia gravis, ms

360
Q

how does graves disease occur?

A

autoantibodies produced against TSH receptors on surface on thyroid cells.
antibody acts as an agonist and stimulates production of thyroid hormones, leading to overactivity of thyroid glands

361
Q

what is hypersensitivity?

A

an immune response that occurs in an exaggerated form causing damage to host tissues

362
Q

what are the 4 types of hypersensitivity responses?

A
  1. type 1- (allergy) immediate involving IgE
  2. type II- (cytotoxic hypersensitivity) antibody initiated
  3. type III (immune complexes)- between antibody and antigen
  4. type IV (delayed type)- mediated by t cells and macrophages
363
Q

describe type 1 hypersensitivity

A

recognised as allergy and people with a genetic predisposition to allergy (atopic)
allergy may be local (reaction to cosmetic) or systemic (reaction to distributed drug)
Known that upon first meeting allergen, no reaction occurs (priming dose) but subsequent encounters cause the reaction (shocking dose)

364
Q

what is the key immunological reaction in type 1 hypersensitivity?

A

involvement of mast cells and IgE isotope of antibody

365
Q

how does damage occur in type 1 hypersensitivity?

A

damage is via inflammatory like reactions

366
Q

what is the difference between type 1 hypersensitivity local and systemic reactions?

A

local reactions are uncomfortable, but systemic can be life threatening, with reaction usually in a matter of minutes from meeting inducing factor (allergen)
- suggests pre formed elements are involved

367
Q

what are the symptoms of allergy

A

nose: sneezing, itching, runny
eyes: redness, itching
lungs: coughing, wheezing, shortness of breath
skin: eczema, hives
GIT: pain, vomiting, diarrhoea, bloating

368
Q

what is anaphylaxis and when does it occur?

A

dramatic allergic reaction with onset rapid symptoms within 15-30 mins
death may occur within a further 15 mins, and persons advised to carry epinephrine pen- raises bp and reduces swelling of airways

369
Q

how can allergies be diagnosed

A
  1. skin prick test- diluted potential antigen given under skin, wheal and flare reaction within 15-30 mins
  2. blood test- Elisa to detect IgE levels
370
Q

what is a distinguishing feature of type II hypersensitivity?

A

distinguishing feature is an antibody (IgM or IgG) response to cell surface bound antigens
- these may be pathological, or may be normal but unwanted, as in blood group transfusion reactions

371
Q

give an example of type II hypersensitivity

A

usually quoted as haemolytic disease of the newborn

372
Q

how does damage occur in type II hypersensitivity

A

damage is usually via complement activation and cell lysis

373
Q

what is the difference between type II and type I hypersensitivity

A

can appear as drug induced type 1 but is much slower, and due to drug binding to cell surface proteins to form a neoantigen

374
Q

what is the distinguishing feature of type III hypersensitivity?

A

involvement of immune complexes, so always involves a soluble antigen
can be autoimmune or non self antigen

375
Q

how does damage occur in type III hypersensitivity

A

damage usually via complement activation and inflammatory response

376
Q

how long does a type III hypersensitivity reaction take to develop

A

as with type 2, reaction takes days to develop

377
Q

how long does type IV hypersensitivity reactions take to develop?

A

slowest of all 4 types, takes 1-2 days to develop

378
Q

what is the distinguishing feature of type IV hypersensitivity?

A

only type caused by the cell mediated response with involvement of Th1, macrophages and Tcyt cells, but not antibody
may be autoimmune or caused by non self antigen

379
Q

how does damage occur in type IV hypersensitivity

A

damage is via CD8 cell and macrophage activity

380
Q

give an example of type IV hypersensitivity and what what it can cause?

A

nickel allergy

can cause chronic disease, but type example is the tuberculin reaction

381
Q

what does chronic inflammation cause?

A

causes an associated increase in airway hyper responsiveness and leads to recurrent episodes of wheezing, breathlessness, chest tightness and coughing

382
Q

what is chronic inflammation and what does it lead to

A

a chronic inflammatory disorder of the airways, leading to reversible airway obstruction
symptoms occur early morning or at night

383
Q

what is IgE and what is it used for?

A

immunoglobulin E is a class of antibody
plays an essential role in type 1 hypersensitivity, which presents during various allergic diseases
also plays a role in allergic conditions, such as anaphylactic reactions to certain drugs/bee stings
present in minute amounts in body, but capable of triggering most powerful inflammatiion reactions

384
Q

what is the role of IgE in asthma?

A

binds to allergens and triggers release of substances from mast cells that can cause inflammation

385
Q

what is allergen exposure

A

repeated exposure to particular allergen can be 1st step in developing a reaction to it

386
Q

what is t cell action

A

allergens induce t cells to activate b cells which develops into plasma cells that produce and release more antibodies

387
Q

name the classifications of asthma

A
  1. extrinsic (atopic/allergic)
  2. intrinsic (non atopic)
  3. based on phenotypes
  4. eosinophilic/non eosinophilic
388
Q

what is the extrinsic classification of asthma?

A

an external trigger that can be identified, childhood asthma, IgE mediated against common environmental antigens (dust, pollen)
acute symptoms
hereditary in 40-60% of cases

389
Q

what is the intrinsic classification of asthma?

A

no obvious causative agent, tends to occur after childhood

more chronic symptoms

390
Q

describe the classification of asthma based on phenotypes

A

eg. allergic (IgE) such as dust mites

non allergic such as pollution, aspirin sensitive, occupational asthma and exercise induced asthma

391
Q

describe the eosinophilic/non eosinophilic classification of asthma

A

type of white blood cell whose natural role is to defend body against parasites
also accumulate wherever allergic reactions take place

392
Q

where do eosinophils gather and what are they responsible for

A

gather wherever there is a parasitic infection/allergic reaction and then release chemicals
the chemicals are very efficient at fighting parasites, but they can also harm the body if released in the wrong place
- the lining of lungs becomes damaged in asthma

393
Q

what are the 2 categories of precipitating factors

A

IgE related- specific precipitating factors, and non IgE related- non specific precipitating factors

394
Q

give examples of IgE related precipitating factors

A

animal allergens- labs/farms, flour/grains- farms/bakers, enzymes- washing powders

395
Q

give examples of non IgE related precipitating factors

A

isocyanides- spray painting, cold air and exercise, airborne irritants (cigarette smoke, fumes, pollution), irritant dust, vapours and fumes, drugs- NSAIDs, beta blockers, infections of the respiratory tract, emotional factors such as stress or laughter

396
Q

what are bronchial provocation tests?

A

increased responsiveness of airways, as measured by a lower FEV/PEFR to stimuli such as inhaled histamine and methacholine

397
Q

what is FEV1?

A

forced expiratory volume- volume of air that can forcibly be blown out in 1 second after full inspiration

398
Q

what is PEF

A

peak expiratory flow- maximal flow achieved during the maximally forced expiration initiated at full inspiration, in L/min or L/sec

399
Q

what does exposure to allergen lead to in pathogenesis

A
  1. a single exposure to allergen causes a dual asthmatic response
  2. repeated exposure to allergens leads to chronic inflammation and bronchoconstriction
400
Q

what are the 2 phases of an asthma attack?

A

acute/early phase response (acute bronchospasm)

late phase response (inflammation)

401
Q

what is the acute/early phase response in an asthma attack?

A

exposure to allergen results in bronchospasm and wheezing within minutes
maximal effect reached within 15-20 minutes and effect subsides after 1-3 hours
may then progress to late phase

402
Q

describe the late phase response in an asthma attack

A

develops about 4 hours after initial acute phase and may last for further 6-8 hours
characterised by eosinophilia in the mucus membrane, mucosal oedema and increases smooth muscle excitability (hyper responsiveness)
airways obstruction with cough and sputum production

403
Q

what changes occurs during a reactive airway disease episode?

A
  1. increased mucus- airways become irritated and inflamed, causing cells in airways to produce mucus (thick mucus produced can clog airways of lung, making it difficult to breath)
  2. inflammation and swelling- airways of lungs swell and become inflamed
  3. muscle tightening- smooth muscles in airways of lungs tighten and airways become smaller, making it more difficult to breathe
404
Q

what is histamine and how does it work?

A

organic nitrogenous compound involved in inflammatory response
increases permeability of capillaries to white blood cells and some proteins, to allow them to engage pathogens in infected tissues
exerts its effects by binding to G protein coupled histamine receptors, designated H1 through H4

405
Q

What are the functions of histamine

A

elicits vasodilation, smooth muscle contraction, mucus hypersecretion and oedema, as part of immediate phase allergic reaction
also has significant immune/proinflammatory properties that are mediated by several cell types (macrophage, t lymphocytes, epithelial and endothelial cells)

406
Q

what does chronic inflammation cause

A

causes airway hyper responsiveness

407
Q

what does chronic inflammation involve

A

involves a host of white blood cells: mast cells, eosinophils, lymphocytes and macrophages

408
Q

what occurs upon mast cell degranulation

A

arachidonic acid metabolites (leukotriene, prostaglandins and cytokines) release occurs

409
Q

what are cytokines and why are they important

A

proteins that are produced by cells
critical elements of immune response and acts as a signal between cells
interact with cells of immune system in order to regulate bodys response to disease and infection

410
Q

describe the roles of cytokines in asthma

A
tumour necrosis factor and interleukin 4, IL5, IL6, IL1B, IL13
profound effects on vascular endothelium (eg. alteration of vascular permeability and adhesiveness)
allowing circulating inflammtory cells to adhere to the endothelium and to migrate into surrounding tissue
IL4, 5 and 6 stimulate the proliferation and differentiation of activated b cells and induces class switch
IL5 is also important in stimulating growth and differentiation of eosinophils
411
Q

describe the process of cell adherence

A
  1. mast cell progenitors must migrate from the blood into tissue sites- crucial step is adherence of cells to endothelium
  2. mediated by adhesion molecules and receptors on surface of mast cells that can mediate binding to other cells and to extracellular matrix
  3. TNF-a and IL4 can modulate adhesion molecules on endothelial cells
  4. activated endothelial cells express the intracellular adhesion molecule, endothelial leukocyte adhesion molecule 1, and vascular cell adhesion molecule on their cell surface
  5. human mast cells express integrins as receptors for these molecules
412
Q

give examples of neutral proteases that mast cells produce and the role of other mast cell mediators

A

eg. tryptase and chymase that damage and activate the bronchial epithelium, contributing to airway wall remodelling
key in host defense, with role in immune surveillance, phagocytosis and immune activation

413
Q

what is a characteristic feature of asthma

A

tissue remodelling

414
Q

how do mast cells affect airway remodelling

A

mast cells may have affect on tissue remodelling on smooth muscle hypertrophy and on mucus hyper secretion, by releasing proteases (tryptase) and growth factors
these cells can also affect epithelial damage, and on basement membrane thickening in patients with allergic asthma

415
Q

how is ongoing mast cell activation detected in asthma

A

detected by elevated levels of tryptase and PGD2 in bronchoalveolar lavage (BAL)

416
Q

describe the clinical characteristics of mast cell degranulation

A

higher spontaneous release of histamine by mast cells obtained from the BAL of asthmatics is observed than those obtained from non asthmatics
ultrastructural analysis of mast cells in lung tissue also shows that asthmatics have more degranulation than atopic non asthmatics

417
Q

what are autocoids? what are they released by?

A

substances produced within the body to help in the remedy of local injuries- locally acting biological factors which are hormone like
released by various stimuli to induce physiological changes such as reddening of the skin, pain, itching, bronchospasm
-these effects can sometimes be undesirable and cause cell death
usually have very brief lifetime and act near site of action

418
Q

what are the functions of autocoids?

A
  1. inflammation
  2. allergic reactions, anaphylactic reactions
  3. neurotransmission
  4. gastric acid secretion
  5. neuroendocrine regulation
    - have CNS properties, they are responsible for bp control
419
Q

what signs of inflammation can autocoids cause?

A

rubor (redness), tumor (swelling), calor (heat) and dolor (pain)

420
Q

what are the 4 types of inflammation

A
  1. type 1- anaphylaxis or allergy
  2. type 2- antibody dependent cytotoxicty
  3. type 3- complex mediated hypersensitivity
  4. type 4- cell mediated hypersensitivity
421
Q

what are the classifications of autocoids?

A
  1. endogenous amines- histamine, seratonin
  2. polypeptides- angiotensin, kinins
  3. lipid derived autocoids- prostaglandins, leukotrienes, thromboxane
422
Q

what is histamine synthesised from and what is it released by

A

synthesised from histidine, stored in granules in mast cell or basophils and released by allergens

423
Q

what does the activation of mast cells release

A

release granules of histamine and heparin

424
Q

how can histamine release occur

A

allergenvia IgE, trauma, side effects of drugs (morphine)

425
Q

what are kinins and how are they synthesised

A

peptide mediators (eg bradykinin), synthesised from kininogen and metabolised by kinases

426
Q

what are the actions of kinins

A

pain, swelling and redness

  • vasodilation and smooth muscle constrictor
  • via a bradykinin receptor (releases eicosanoids- prostaglandins)
427
Q

what are eicosanoids made of and what are their roles

A

signalling molecules made by oxidation of 20 carbon fatty acids
complex control over inflammation or immunity and as messengers in CNS
- platelet activating factpr
- prostaglandins, leukotrines

428
Q

what do mast cells release

A

histamine, leukotrienes, prostaglandin D2, PAF, TNFa, kallikrein

429
Q

what do antihistamines do and give examples of antihistamines

A

block H1 receptor a 7TMG protein coupled receptor

  • eg. chlorphenamine, hydroxyzine and promethazine (drowsy)
  • cetirizine, loratidine and fexofenadine (non drowsy)
430
Q

describe the properties of the platelet activating factor

A

1st phospholipid known to have messenger functions
derived from membrane bound lipids in basophils, monocytes, neutrophils and platelets
continuously produced but in low amounts and production is controlled by activity of PAF acetylhydrolases
produced in larger quantities by inflammatory cells

431
Q

what are the functions of PAF

A
  1. activates platelets
  2. bronchospasm
  3. chemotactic for white blood cells
  4. hyperalgesia (dolor)
  5. odema (tumor)
432
Q

what are prostaglandins and what do they consist of

A

group of hormone like lipid compounds that are derived enzymatically from fatty acids
contains 20C atoms, including a 5 carbon ring

433
Q

what is the role of prostaglandins

A

mediators of many physiological effects such as regulating the contraction and relaxation of smooth muscle tissues
act in an autocrine or paracrine manner
hyperalgesia- sensitise nerve endings to painful stimuli
inflammation: dilate arterioles, constrict venules, increase capillary permeability and leakiness

434
Q

what is the role of prostaglandins in the stomach

A

decrease acid secretion and increase mucous secretion (gastroprotective)

435
Q

what is the role of prostaglandings in kidneys

A

increase blood flow and increase Na+ and H2O excretion (diuretic)

436
Q

what are the vascular effects of prostaglandins

A

vasodilation and inhibit platelet aggregation

437
Q

what are the therapeutic uses of prostaglandins

A

obstetrics, gastric ulcers, glaucoma

438
Q

what are non steroidal anti inflammatory drugs

A

anti inflammatory, analgesics and antipyretics

types: ibuprofen, naproxen, diclofenac, aspirin

439
Q

what are the side effects of NSAIDs

A
  1. peptic ulcers- inhibit gastric protection by prostaglandins
  2. renal damage (papillary necrosis)- decreases renal blood flow, causing salt and water retention
  3. hypertension
  4. headaches
  5. allergic reactions
440
Q

what is cyclooxygenase and what are their roles?

A

enzymes that produce prostaglandins
2 types of COX enzymes
COX 1 and 2 produce prostaglandins that promote inflammation, pain and fever

441
Q

what is a feature of only COX 1 enzymes

A

only COX 1 produces prostaglandins that activate platelets and protect the stomach and intestinal lining

442
Q

describe the effect that NSAIDs have on COX enzymes

A

NSAIDs block the cox enzymes and lower the production of prostaglandins

443
Q

how are inflammation, pain and fever decreased

A

lowered by all cox inhibitors

444
Q

what do older NSAIDs block? what do newer NSAIDs block?

A

both COX 1 and 2

newer cox 2 inhibitors only block cox 2 enzyme

445
Q

what is a benefit of using newer cox 2 inhibitors

A

since cox 2 inhibitors dont block cox 1, they dont cause ulcers or increase risk of bleeding as much as older NSAIDs
cox 2 inhibitors are as effective as older NSAIDs for treating inflammation, pain and fever

446
Q

how are leukotrienes produced and what do they trigger?

A

by the oxidation of arachadonic acid and the essential fatty acid, EPA, by the enzyme lipooxygenase
triggers contractions in smooth muscles lining the bronchioles

447
Q

what is the overproduction of leukotrienes a cause of?

A

major cause of inflammation in asthma and allergic rhinitis

448
Q

what do leukotrienes use to communicate with cells

A

use lipid signalling to communicate to the cell producing them (autocrine) or neighbouring cells (paracrine) to regulate immune responses

449
Q

what are leukotriene antagonists

A

used to treat asthma by inhibiting the production or activity of leukotrienes
eg. montelukast, zafirlukast

450
Q

what is the most important glucocorticosteroid

A

cortisol- binds to the GR and activates gene transcription
also non genomic effect
eg. src kinase binds to inactive GR, released via cortisol binding and phosphorylates proteins, resulting in decreased creatin of AA

451
Q

What do corticosteroids do

A

lower inflammation in airways that carry air to lungs and lower the mucus made by bronchial tubes, making it easier to breath
regulates/supports variety of cardiovascular, immunological, metabolic and homeostatic functions
various synthetic glucocorticosteroids are available and used as either replacement therapy in glucocorticosteroid deficiency or to suppress immune system

452
Q

what are the anti inflammatory effects of glucocorticosteroids?

A
  1. increase lipocortin- inhibits phospholipase A2
  2. decreases cox2 expression
    decreases cytokine production
    decreases IgG production
    inhibits macrophages and neutrophils
    lowers t helper cell activity
453
Q

describe the aetiology of COPD

A
  1. Genetic factors- a1 antitrypsin deficiency
  2. age
  3. occupation
  4. air pollution
  5. socioeconomic status
  6. biggest risk factor= smoking
454
Q

what is meant by one pack year

A

smoking 20 cigarettes per day for one year

number of pack years= (number smoked per day x number of years smoked/20)

455
Q

what are the characteristics of pink puffer type A

A
  1. increased alveolar ventilation
  2. PaO2
  3. lowers PaCO2
  4. breathless
456
Q

describe the properties of blue bloater type B

A
  1. decreases alveolar ventilation
  2. lowers PaO2
  3. Lowers Paco2
  4. not breathless
  5. rely on hypotoxic drive to maintain respiration as their respiratory centres are desensitised to increased PaCO2
457
Q

what are the clinical symptoms of cOPD

A

Cough, sputum and dyspnoea

458
Q

what are the signs of COPD

A

tachypnoea, hyperinflation, wheeze, cyanosis, cor pulmonale

459
Q

what are the complications of COPD

A

acute exacerbations +/- infection, polycythaemia, cor pulmonale, respiratory failure

460
Q

how is COPD assessed

A
  • spirometry
  • bronchodilator response
  • trial of oral steroids
  • CXR
461
Q

describe the non pharmalogical treatment of COPD

A
  • stop smoking
  • exercise
  • influenza and pneumococcal vaccine
462
Q

describe the pharmacological treatment of COPD

A
  1. mild COPD- antimuscarinics (eg. ipatropium inhaled prn)
  2. moderate- regular antimuscarinics or long lasting B2 agonist
    - inhaled steroid if FEV1<50%> 2 exacerbations per year
  3. severe- combined therapy, regular short acting b2 agonist with ipatropium
    - consider steroid trial
    - assess for home nebuliser
463
Q

what treatment options would be suggested for more advanced COPD

A
  • pulmonary rehab (multidisciplinary team)
  • theophylline (monitor levels)
  • consider LTOT if PaO2 <7.3 kpa
  • check home support
  • treat depression
464
Q

describe the management of acute exacerbations of COPD

A
  • controlled o2 therapy start at 24-28% monitor ABG
  • nebulised bronchodilators salbutamol and ipatropium
  • steroids IV hydrocortisone and oral prednisolone
    antibiotics for infection
  • physiotherapy to aid sputum expectroration
  • if no response, repeat nebulisers, IV aminophylline
465
Q

what is involved in the diagnosis of asthma

A
  1. clinical assessment involving history of recurrent episodes
  2. symptoms of wheeze, cough and breathlessness
  3. personal and family history
  4. no symptoms/signs to suggest alternate diagnosis
466
Q

what are the signs and symptoms of asthma

A

wheezing, cough, shortness of breath, tightness in chest and night time awakenings

467
Q

name the lung function tests

A

FEV1, FVC (forced vital capacity), PEF

Bronchodilator administered and would expect to see increase in FEV1

468
Q

name the treatments used for asthma

A

SABA: salbutamol used as reliever of symptoms
ICS: beclomethasone used as preventor of symptoms
LABA: salmeterol used as additive treatment
LTRA: montelukast used as additive treatment

469
Q

what determines whether asthma is controlled vs uncontrolled

A

based on symptoms and frequency of symptoms

less symptoms= more controlled

470
Q

what is the step down guidance

A

adults stable on high dose ICS should reduce dose by 25-50% every 3 months
- regular reviews to ensure overtreatment doesnt occur
points to consider: severity, benefits seen from treatment, length of treatment and patients preference